Harderwykenburg

The Harderwykenburg is a medieval stone house in Leer constructed with stones salvaged from a former monastery, its exterior walls measuring between 0.96 and 1.23 meters thick. The structure combines an original tower section with a two-story extension that was added at a later period.

Construction began after 1450 as a stronghold for chieftain Hayo Unken, then passed to Dietrich Harderwyk in 1588 through marriage to Unken's granddaughter. This transition reflects how power and property shifted through family alliances in the region during that time.

This structure is a steenhuis, a fortified dwelling type that was common in East Frisia, featuring a tower with a later two-story extension added to one side. The thick walls and sturdy design reflect how wealthy families of that era protected themselves and their property from raids.

The house sits at Alte Marktstraße 3 in Leer's old town and retains its original medieval structure. Visitors can walk around the exterior to appreciate the fortress-like design and the gardens surrounding the property.

The original structure measured 8.09 by 11.13 meters, making it one of the most thoroughly documented medieval stone houses in East Frisia. These precise measurements come from historical records that have allowed researchers to understand exactly how the building originally looked.